(Z)-octadec-9-enol

Endpoint summary

Description of key information

The key result for acute toxicity was read across from hexadecan-1-ol (CAS 36653-82-4), reporting an LD50 value of >2000 mg/kg (Hempstock 1996; rel 1). This is supported by data on the substance Alcohols, C16-18 and C18-unsat., which contained between 40 and 90% of unsaturated octadecan-1-ol, which indicates that the LD50 was >5000 mg/kg bw (Henkel KGaA. 1981h) .  
The acute dermal toxicity was read across from 1-tetradecanol (CAS 112-72-1), reporting an LD50 value of 8000mg/kg (Scientific Associates 1977; rel 2). 
Data for the inhalation toxicity endpoint were not available, but further testing was not scientifically justifiable since sufficient information via the oral and dermal endpoints was available. Further more, weight of evidence across category suggests the LC50 to be expected to be greater than the substantially saturated vapour concentration..

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

8 000 mg/kg bw

Additional information

The LC₅₀ for inhalation toxicity is expected to be greater than the substantially saturated vapour concentration, based on weight of evidence across category of other linear alcohols. The available information includes data on C12 -16, C14 (tetradecan-1-ol), C16 (hexadecan-1-ol), C16 -18, C18 (octadecan-1-ol), and C20 (eicosan-1-ol).

The key study for acute oral toxicity is read across from hexadecan-1-ol which has been tested for acute oral toxicity in a study conducted according to OECD 401 and in compliance with GLP (Hempstock 1996; rel 1). No deaths occured and no evidence of toxicity was observed when 10 male and 10 female rats were dosed with 2000 mg/kg bw of hexadecan-1-ol by oral gavage. It was concluded that the rat oral LD50 was >2000 mg/kg bw.

The key acute oral study is supported by data on the substance Alcohols, C16-18 and C18-unsat., which contained between 40 and 90% of unsaturated octadecan-1-ol. Only a summary was available for review. Five animals per sex were dose by gavage with 5000 mg/kg bw in a study conducted according to OECD 401 and in compliance with GLP; only a summary was available for review. No deaths occurred and therefore the LD50 was determined to be >5000 mg/kg bw (Henkel KGaA. 1981h).

The key acute dermal study is read across from tetradecan-1-ol (CAS 112-72-1). The study predates the OECD guideline was conducted according to a protocol similar to the guideline. No deaths were reported when two male and two female rats were exposed occlusively to 2, 4 and 8 g/kg bw for 24 hours. The test substance was applied to abraded skin in one animal of each sex . The animals were observed for 14 days after exposure. One male and one female rabbit died in the high dose group only, so it was concluded that the LD50 was 8000 mg/kg bw (Scientific Associates 1977; rel 2). Both deaths occurred in animals where the test substance had been applied to abraded skin.

Discussion of trends in the Category of C6-24 linear and essentially-linear aliphatic alcohols:

Acute toxicity tests of the linear and essentially linear alcohols do not indicate any potential hazard for acute, dermal or inhalation toxicity. Tests on various substances included in this category are all supportive of these results and do not warrant classification for most of the acute toxicity endpoints under GHS criteria. The majority of the substances are therefore not classified for acute toxicity in accordance with EC regulation 1272/2008. The only exception to this is hexan-1-ol, which finds that the acute dermal data for the test substance are consistent with Acute dermal tox category 4 and Acute oral tox 4 H302/R22, in line with the Annex VI entry.

Justification for selection of acute toxicity – oral endpoint
The selected study was conducted according to an appropriate OECD guideline and in compliance with GLP.

Justification for selection of acute toxicity – dermal endpoint
The selected study was conducted according to a protocol that is similar to an appropriate OECD guideline/

Justification for classification or non-classification

Based on the above information, there is no requirement for classification or labelling of (Z)-octadec-9-enol for any of the acute toxicity endpoints, in accordance with CLP Regulation (EC) No. 1272/2008.